Added unit test for lambdify
Added unit test for lambdify

Removed the plotting test for Max(x, 5) replacing it with a unit
test for lambdify

MechCoder/sympy,AunShiLord/sympy,souravsingh/sympy,Designist/sympy,maniteja123/sympy,cccfran/sympy,jamesblunt/sympy,asm666/sympy,Davidjohnwilson/sympy,hargup/sympy,beni55/sympy,farhaanbukhsh/sympy,skidzo/sympy,ChristinaZografou/sympy,Davidjohnwilson/sympy,yashsharan/sympy,moble/sympy,Arafatk/sympy,pandeyadarsh/sympy,aktech/sympy,kaichogami/sympy,atreyv/sympy,Mitchkoens/sympy,kevalds51/sympy,MridulS/sympy,abloomston/sympy,oliverlee/sympy,Vishluck/sympy,dqnykamp/sympy,moble/sympy,Sumith1896/sympy,atsao72/sympy,Shaswat27/sympy,VaibhavAgarwalVA/sympy,rahuldan/sympy,jamesblunt/sympy,kaushik94/sympy,maniteja123/sympy,bukzor/sympy,emon10005/sympy,liangjiaxing/sympy,Curious72/sympy,postvakje/sympy,AkademieOlympia/sympy,shipci/sympy,oliverlee/sympy,yukoba/sympy,aktech/sympy,skidzo/sympy,Curious72/sympy,bukzor/sympy,chaffra/sympy,farhaanbukhsh/sympy,meghana1995/sympy,kmacinnis/sympy,saurabhjn76/sympy,lindsayad/sympy,Vishluck/sympy,cswiercz/sympy,mafiya69/sympy,abhiii5459/sympy,yashsharan/sympy,iamutkarshtiwari/sympy,moble/sympy,asm666/sympy,farhaanbukhsh/sympy,cswiercz/sympy,wyom/sympy,debugger22/sympy,kaichogami/sympy,toolforger/sympy,shikil/sympy,mafiya69/sympy,Davidjohnwilson/sympy,garvitr/sympy,Shaswat27/sympy,vipulroxx/sympy,shipci/sympy,abloomston/sympy,abhiii5459/sympy,jerli/sympy,debugger22/sympy,Titan-C/sympy,sampadsaha5/sympy,jbbskinny/sympy,aktech/sympy,lidavidm/sympy,kaushik94/sympy,garvitr/sympy,garvitr/sympy,wanglongqi/sympy,chaffra/sympy,atreyv/sympy,maniteja123/sympy,AkademieOlympia/sympy,wanglongqi/sympy,meghana1995/sympy,cccfran/sympy,mcdaniel67/sympy,kumarkrishna/sympy,emon10005/sympy,Mitchkoens/sympy,abloomston/sympy,bukzor/sympy,ga7g08/sympy,wyom/sympy,cswiercz/sympy,hargup/sympy,madan96/sympy,madan96/sympy,drufat/sympy,Titan-C/sympy,wanglongqi/sympy,pbrady/sympy,grevutiu-gabriel/sympy,sahmed95/sympy,hrashk/sympy,atsao72/sympy,liangjiaxing/sympy,jaimahajan1997/sympy,Curious72/sympy,kmacinnis/sympy,AunShiLord/sympy,lidavidm/sympy,MridulS/sympy,saurabhjn76/sympy,chaffra/sympy,oliverlee/sympy,Arafatk/sympy,drufat/sympy,jerli/sympy,yukoba/sympy,kaushik94/sympy,lindsayad/sympy,diofant/diofant,Vishluck/sympy,sunny94/temp,hargup/sympy,sampadsaha5/sympy,VaibhavAgarwalVA/sympy,atsao72/sympy,kaichogami/sympy,mcdaniel67/sympy,Mitchkoens/sympy,jamesblunt/sympy,saurabhjn76/sympy,postvakje/sympy,shikil/sympy,sahmed95/sympy,kmacinnis/sympy,emon10005/sympy,Designist/sympy,toolforger/sympy,ahhda/sympy,Shaswat27/sympy,cccfran/sympy,shikil/sympy,jbbskinny/sympy,asm666/sympy,sahmed95/sympy,lidavidm/sympy,Designist/sympy,sunny94/temp,jaimahajan1997/sympy,MechCoder/sympy,souravsingh/sympy,grevutiu-gabriel/sympy,atreyv/sympy,madan96/sympy,liangjiaxing/sympy,Sumith1896/sympy,dqnykamp/sympy,iamutkarshtiwari/sympy,MridulS/sympy,VaibhavAgarwalVA/sympy,lindsayad/sympy,ga7g08/sympy,sahilshekhawat/sympy,toolforger/sympy,skirpichev/omg,skidzo/sympy,Gadal/sympy,pandeyadarsh/sympy,jerli/sympy,Sumith1896/sympy,yashsharan/sympy,ChristinaZografou/sympy,hrashk/sympy,kumarkrishna/sympy,postvakje/sympy,vipulroxx/sympy,sahilshekhawat/sympy,Titan-C/sympy,sunny94/temp,sahilshekhawat/sympy,jaimahajan1997/sympy,dqnykamp/sympy,sampadsaha5/sympy,rahuldan/sympy,mcdaniel67/sympy,kevalds51/sympy,drufat/sympy,yukoba/sympy,ChristinaZografou/sympy,beni55/sympy,kumarkrishna/sympy,rahuldan/sympy,pbrady/sympy,ga7g08/sympy,MechCoder/sympy,jbbskinny/sympy,abhiii5459/sympy,ahhda/sympy,debugger22/sympy,Arafatk/sympy,pbrady/sympy,Gadal/sympy,AkademieOlympia/sympy,Gadal/sympy,mafiya69/sympy,meghana1995/sympy,souravsingh/sympy,beni55/sympy,ahhda/sympy,AunShiLord/sympy,iamutkarshtiwari/sympy,vipulroxx/sympy,shipci/sympy,hrashk/sympy,grevutiu-gabriel/sympy,kevalds51/sympy,wyom/sympy,pandeyadarsh/sympy